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Give 1 characteristic for: Alkali Metals, Alkaline Earth Metals, Halogens, Neon Gases, and Hydrogen.
A few examples are...
Alkali Metals: Soft, low density, 1+ charge, Not found free in nature
Alkaline earth metals: 2+ charge, Hard, low density, very reactive
Halogens: Bright coloured, not found naturally, all toxic, 1- charge
Noble gases: non reactive, colourless, very low boiling point
Hydrogen can either be 1+ or 1-, most common element in the universes, lowest of all known elements, colourless